P-alkenyloxybenzoic acid esters useful for the control of insects

ABSTRACT

P-Alkenyloxybenzoic acid esters useful for the control of insects.

Unite Sites mm [191 Siddall Feb. 25, 1975 P-ALKENYLOXYBENZOIC ACIDESTERS [56] References Cited USEFUL FOR THE CONTROL OF INSECTS UNITEDSTATES PATENTS [75] Inventor; John B. Siddall, Palo Alto, Calif3,712,913 1/1973 Chodnekar 260/470 [73] Assignee: Zoecon Corporation,Palo Alto, OTHER PUBLICATIONS Calif. Thomae, C. A., 60, 2865g (1964).[22] Filed: Dec. 4, 1972 Upjohn & Co., C. A., 56, 8646g (1962). [21]Appl. No.: 311,572 Primary Examiner-Lorraine A. Weinberger AssistantExaminerJohn F. Terapane ReIfned Apphcatlon Data Attorney, Agent, orFirm-Donald W. Erickson; [63] Continuation of Ser. No. 60,636, Aug. 3,1970, Lee Louise Priest abandoned.

[52] US. CL... 260/473 R, 260/340.9, 260/4l0.9 R, [57] ABSTRACT 260MB,260520, 260/521 R 260/593 R, p-Alkenyloxybenzmc acid esters useful forthe control 260/614 R, 260/632 R, 260/654 R, 424/308,

424/317 [51] Int. Cl. C07c 69/78 [58] Field of Search 260/473 R, 521 R,520, 8 Claims, N0 Drawings 260/521 B, 473 RS P-ALKENYLOXYBENZOIC ACIDESTERS USEFUL FOR THE CONTROL OF INSECTS This is a continuation of US.application Ser. No. 60,636, filed Aug. 3, 1970 now abandoned.

This invention relates to novel phenyl compounds, 5 syntheses thereofand methods and compositions for the control of insects.

The phenyl compounds of the present invention are those of the formulasI, 11, Ill and 1V:

i f R4-C-(CH C1-l-W-R 11) R R2 R 'i3-(CH -$-CH- (C1-lz) N-R 7' 111 R Z pl i R (|3-(CH -CH N-R (IV) wherein,

R1 is the group each of R R and R is lower alkyl;

R is -OR in which R is hydrogen, lower alkyl or aralkyl;

R is lower alkyl, cycloalkyl, aralkyl or OR in which R is hydrogen,lower alkyl, cycloalkyl or aralkyl;

W is oxygen, sulfur, sulfinyl or sulfonyl;

each of Z and z is hydrogen or taken together a carbon-carbon doublebond;

m is one or two;

n is three or four; and

p is one or two.

The term lower alkyl, as used herein, refers to primary or secondaryalkyl having a chain length of one to six carbon atoms, straight orbranched chain, such as methyl, ethyl, n-propyl, i-propyl, n-butyl,i-butyl, sbutyl, n-pentyl, i-hexyl and n-hexyl. The term aralkyl," asused herein, refers to aralkyl of seven to 12 carbon atoms, such asbenzyl, phenethyl, methylbenzyl and naphthylmethyl. The term cycloalkyl,as used herein, refers to cycloalkyl group of four to eight carbonatoms.

The compounds of formulas I, II, III and IV are useful for the controlof insects. They are applied using liquid or solid carriers and,preferably, at a time so as to contact the immature insect during theembryo, larvae or pupa stage of the insects life. The control of insectscan be brought about by such treatment as contact of the insect with thecompound by direct topical contact, vapor contact, contact throughingestion or transmittal from one insect to another through physicalcontact. For example, topical application, as by spraying, of a compoundof the present invention to an insect during the egg, larvae or pupastage effectively inhibits the normal passage of the immature insect tothe next metamorphic stage. In some cases, complete inhibition isobtained and in other cases partial inhibition occurs resulting in animperfect insect which is unable to reproduce. The compounds can be usedat very low dosage levels of the order of 0.001 pg. to 10 ug. perinsect. In the application of the compounds, the application can be suchas to apply lower or higher dosages of the aforementioned range based onsuch factors as the estimated insect population, environmentalconditions, locus of the insects and previous trials. Carriers, such aswater, mineral and vegetable oils, e.g., refined kerosene, xylene,toluene, cottonseed oil, sesamol, and the like, and solid carrier's,such as silica, talc, resins, synthetic polymers, can be used to dilutethe active ingredient. Insect attractants or pheromones can also beincluded. Emulsifying agents and wetting agents can be used informulations of the compounds to assist in application. Generally, theformulation will contain less than percent by weight of the activecompound and more frequently less than 25 percent.

Typical insects which can be controlled by treatment with the compoundsof the present invention are bugs of the family Miridae, such as Lygusbugs; Diptera, such as Aedes aegypti, Aphididae, such as melon aphid andcabbage aphid; Periplaneta americana, Galleria mellonella, Tenebriomolitor, Tribolium confusum, Oncopeltus fasciatus, Phthorimoeaoperculella (potato tubermoth), Dysdercus, Hypera postica, Manduca sextaand Heliothis Zea.

Depending upon the particular insect being treated and the particularstage of the life cycle at the time of treatment, control of insects bytreatment with a compound of the present invention is attributed to thecompounds activity to: inhibit metamorphosis; act as a directinsecticide, particularly at the embryo stage; act as a chemosterilant;or break the diapause of the insect.

Although not intending to be limited by a theoretical explanation, itappears that the effectiveness of the compounds of the present inventioncan be traced to their ability to mimic the activity of juvenile hormonesubstances. Juvenile hormone has been identified as methyl 10,1l-(cis)oxido-7-ethyl-3,1 l-dimethyltrideca- 2(trans),6(trans)-dienoate(Roeller et al., Angew. Chem. internat. Edit, 6, 179 (1967) and methyl10,11- (cis)oxido-3,7,1 1-trimethyltrideca-2(trans),6(trans)- dienoate(Meyer et al., Proc. N.A.S. (US) 60, 853 (1968). Juvenile hormoneanalogs have been described in Life Sciences 4, 2323 (1965); Romanuk etal., Proc. N.A.S. (US) 57, 349 (1967); Science 164, 323 (1969); US. Pat.Nos. 3,429,970 and 3,453,362; Canadian Pat. No. 834,191 and Wakabayashi,J. Med. Chem. 12, 191 (1969).

1n the application of the compounds of the present invention involvingisomerism, there is usually employed a mixture of isomers. As individualisomers, the trans isomer (i.e., when 2 and Z form a double bond) ispreferably employed for the control of insects.

The compounds of the present invention can be conveniently prepared fromthe corresponding olefin using mercuric salt followed by reduction ofthe oxymercurial intermediate in situ. Thus, an olefin of the formula(n' is two or three):

is reacted with, for example, mercuric acetate in aqueous ether followedby reduction to yield the corresponding compound of formula I, II, IIIor IV in which R is OH. By conducting the reaction in the presence ofthe appropriate alcohol, the corresponding ether is obtained. Suitablemercuric salts include mercuric acetate, mercuric nitrate, mercurictrifluoroacetate, mercuric acylates and mercuric halides. Suitablereducing agents include the borohydrides, hydrazine and sodium amalgam.See Brown and Rei, J. Am. Chem. Soc. 91,

conversion of the olefine I, II, III and IV into the compounds of thepresent invention.

In the case of compounds wherein R is alkyl, cycloalkyl, or aralkyl,i.e., the ketones reduction of the carbonyl group may occur. Thus theketones are prepared by reaction of the acid (R is OR in which R ishydrogen) with the appropriate organo lithium compound after theforegoing reaction is completed.

The starting compounds I and II, in which W is oxygen, can be preparedby the reaction of alkyl 4- hydroxybenzoate with a bromide or chlorideof the formula V or VI (X is bromo or chloro):

in which R is hydrogen or lower alkyl and m is zero or one, usinglithium aluminum hydride, or the like. The overall synthesis can beoutlined as follows:

l,3 3 l,2 R -c=o Wittig R4.-L=CH- (cn ;c=o

( (VIII) R C en (cn ,cn on is v 2 v1 R cu (cn ,c cn (cu OH 5646 (1969);Brown and Kurek, J. Am. chem. Chem. Soc. 91, 5647 (1969); Lattes andPerie, Tetrahedron Letters, No.51, 5165 (1967); J. Amer. Chem. Soc. 89,

1522 and 1524 (I967); Perie and Lattes, Bulletin De 65 La SocieteChimique De France, No. 2, 583 (1970) and Lattes and Perie, CR. Acad.Sci. Paris 262, 1591 (1966) in which there is described suitable methodsfor In the practice of the above process, a dialkyl ketone of formulaVII is reacted with a Wittig reagent of formula VII (0 is phenyl) toform the ethylene ketal of a compound of formula VIII which ishydrolyzed by treatment with acid to the ketone (VIII). The ketone(VIII) is then reacted with the carbanion of dialkylcarbalkoxyphosphonate to yield the a,,B-unsaturated ester (IX) (m' iszero and R is lower alkyl) or with B-carboxyethyltriphenylphosphoniumchloride in the presence of base to yield the fiy-unsaturated acid (IX;m is one and R is hydrogen). Suitable conditions are described in myapplication Ser. No. 7,987, filed Feb. 2, 1970, now US. Pat. No.3,697,565, and by H. S. Corey et al., J. Am. Chem. Soc. 86, 1884-1885 (1964), the disclosures of which are incorporated by reference. The acidor ester (IX) is then reduced by conventional techniques using lithiumaluminum hydride or like reducing agent to yield the primary alcohol (X)which is converted to the C-1 bromide or chloride (V) using phosphorustrichloride, phosphorus tribromide, phosphorus pentachloride, phosphoruspentabromide, or the like. Compounds of formula V can be prepared alsousing the synthesis of Bowers, Science 164, 323-325 (I969) which isincorporated by reference. The compounds of formula XI are prepared byreduction of the ketone (VIII) using sodium borohydride, lithiumaluminum hydride, or the like, and the conversion of the secondaryalcohol (XI) into the bromide or chloride (VI) using phosphorustribromide or phosphorus trichloride.

The thio compounds of formulas I' and H (W is sulfur) can be prepared bytreating a bromide or chloride of formula V or VI with the appropriatemercaptan in the presence of sodium hydroxide, sodium alkoxide, and thelike. Alternatively, the halide V or VI is converted to thecorresponding thiol by treatment with hydrogen sulfide in alcohol in thepresence of base, such as sodium hydroxide. The thus-obtained aliphaticthiol on treatment with sodium-hydroxide, droxide, or the like,furnishes the corresponding alkali mercaptide with on treatment with thebromide or chloride of the formula X-R furnishes the thioethers orsulfides of formulas I' and II (W is sulfur).

The sulfinyl compounds are prepared by treatment of a thioether withsodium metaperiodate, hydrogen peroxide, or the like, at a temperatureof from about 0 to C for about I to 6 hours. The reaction usuallyaffords some of the sulfonyl compound also which can be separated bychromatography. By using more than 1 mole of sodium periodate orhydrogen peroxide, higher temperature and longer reaction time, thereaction favors formation of the sulfonyl compounds. Preparation ofsulfinyl and sulfonyl compounds is described by N. J. Leonard et al.,Journal of Organic Chemistry 27, 282 (1962).

The amines of formulas III and IV are prepared by the reaction of ahalide of formula V or VI with alkyl 4-aminobenzoate. The reactionusually affords a mixture of secondary and tertiary amines, the tertiaryamine being favored by using an excess ofthe halide V or VI.

An alternative process for the preparation of compounds of the formulasI, II, III or IV is to perform the addition of water or alcohol, usingthe mercuric salt.

process described above, on a compound offormula V, VI or IX andthereafter perform the alkylation step.

The following examples are provided to illustrate the practice of thepresent invention and the preparation of the novel compounds.Temperature in degrees Centigrade.

potassium hy- EXAMPLE 1 A. 3,7-Diethylnona-2,6-dien-1-ol (4.8 g.) isdissolved in 40 ml. of ether, cooled to -50 and 2.44 g. of phosphorustribromide in 5 ml. of ether is added over 20 minutes. The reactionmixture is stirred for 2 hours, poured onto ice and extracted withether. The ethereal extracts are combined, washed with 10 percent sodiumcarbonate, water and saturated sodium chloride, dried over sodiumsulfate and the solvent concentrated to yieldl-brom0-3,7-diethylnonaF2,6-diene.

B. Three grams of methyl P-hydroxybenzoate and 4 g. oflbromo-3,7-diethylnona-2,6-diene are added at about 20 at methanolicsodium methoxide (0.5 g. of sodium and 7 ml. of methanol) and themixture refluxed for five hours. After cooling to about 20, the sodiumbromide is filtered off and the filtrate concentrated. The contentrateis diluted with water and then extracted with ether. The etherealextracts are com: bined, dried over sodium sulfate and evaporated underreduced pressure to yield methyl 4-(3,7-diethylnona-2,6-dienyloxy)benzoate which can be purified by chromatography.

C. The procedure of Part A is repeated with the exception of using anequal amount of the C-1 alcohols listed in Column Ito afford thecorresponding C-l bromide listed in Column II.

3,7-dimethylocta-2,6-dien- 1 -ol, 3-methyl-7-ethylnona-2,6-dien- 1 -ol,3,7-dimethylnona-2,6-dien- 1 -ol, 4-methyl-8-ethyldeca-3 ,7-dien- 1 -ol,4,8 dimethyldeca-3,7-dien- 1 -ol, 4,8-dimethylnona-3 ,7-dien- 1 -ol,1,5-dimethylhex-4-en- 1 -01,

3 ,7-dimethyloct-6-en- 1 -ol,

III

methyl 4-(3 ',7'-dimethylocta-2 ',6'-dienyloxy)- benzoate,

methyl 4-(3 -methyl-7 -ethylnona-2 ',6-dienyloxy)- benzoate,

methyl 4-( 3 ',7-dimethylnona-2 ',6-dienyloxy benzoate,

methyl 4-(4'-methyl-8'-ethyldeca-3 7'-dienyloxy benzoate methyl4-(4,8-dimethyldeca-3 ',7 -dienyloxy)- benzoate 7 methyl 4-(4,8 -dimenthylnona-3 ',7 -dienyloxy)- benzoate,

EXAMPLE 2 A. To a solution of 2 g. of methyl 4-(3,7'-dimethylocta-2,6-dienyloxy)benzoate in 20 ml. of ethanol, cooled to byan ice bath, is added a suspension of 2.32 g. of mercuric acetate in 50ml. of ethanol over minutes. The reaction mixture is stirred for twohours and then, with cooling, 1.22 g. of potassium hydroxide in ml. ofethanol is added. Then 0.139 g. of sodium borohydride is added in smallportions and stirring continued minutes. The soltution is decanted, thenconcentrated to half volume, diluted with 100 ml. of water and extractedwith ether (3 X 50). The ethereal phase is washed with water, dried overmagnesium sulfate, and the crude product chromatographed on silica'using hexanezether to yield methyl 4-(3,7-dimethyl-7-ethoxyoct-2'-enyloxy)benzoate.

B. The foregoing process of Part A is repeated with the exception ofreplacing methyl 4-(3,7'- dimethylocta-2',6-dienyloxy)benzoate with anequal amount of each of:

methyl 4-( 3 ',7 '-diethylnona-2 ',6 -dienyloxy)- benzoate,

methyl 4-(3-methyl -7-ethylnona-2,6-dienyloxy)- benzoate,

methyl benzoate,

methyl 4-(4"methyl-8'-ethyldeca-3,7-dibenyloxy)- benzoate,

4-( 3 ',7 '-dimethylnona-2,6'-dienyloxy)- methyl 4-(4,8 dimethyldeca-3',7 '-dienyloxy benzoate,

methyl 4-(4,8 -dimethylnona-3 ',7-dienyloxy)- benzoate,

methyl 4-(] ',5'-dimethylhex-4-enyloxy)-benzoate, methyl4-(3',7-dimethyloct-6-enyloxy)-benzoate to yield methyl 4-( 3',7-diethyl-7-ethoxynon-2-enyloxy)- benzoate 7 I 7 methyl 4-( 3'-methyl-7 '-ethyl-7 -ethoxynon2'- enyloxy)-benzoate,

methyl 4-(3',7'-dimethyl-7-ethoxynon-2-enyloxy)- benzoate,

methyl 4-(4-methyl-8-ethyl-8-ethoxydec-3'- enyloxy)-benzoate,

methyl 4-(4',8-dimethyl-8'-ethoxydec-3-enyloxy)- benzoate,

methyl 4-(4,8-dimethyl-8-ethoxynon-3-enyloxy)- benzoate,

methyl 4-(1',5 '-dimethyl-5 '-ethoxyhexanyloxy)- benzoate, and

methyl 4-( 3 ',7'-dimethyl-7 -ethoxyoctanyloxy)- benzoate.

By use of each of methanol, n-propanol, i-propanol or n-butanol in theforegoing process of this example in place of ethanol, the correspondingalcohol additives are obtained. For example, the use of an equal amountof methanol, n-propanol, i-propanol or n-butanol in place of ethanol inPart A yields each of methyl 4(3',7-dimethyl-7-methoxyoct-2'-enyloxy)benzoate, methyl 4-[3',7'-dimethyl-7-(n-propoxy)oct-2'-enyloxy]benzoate, methyl4-[3,7-dimethyl-7-(ipropoxy)oct-2'-enyloxy]benzoate, respectively.

i 8 EXAMPLE 3 To a mixture of 1.9 g. of mercuric acetate, 6 ml. of waterand 20 ml. of tetrahydrofuran is added 1.49 g. of methyl4-3',7'-diethylnona-2,6-dienyloxy)benzoate slowly. After addition iscomplete, the reaction mixture is stirred for about 20 minutes. Themixture is cooled to about 0 and 6 ml. of aqueous sodium hydroxide (3molar) is added followed by 0.49 g. of sodium hydroxide (about 3 molar).The mixture is stirred for about 30 minutes. The mixture is thendecanted, concentrated,

diluted with water and then extracted with ether. The

ethereal extract is washed with water, dried over magnesium sulfate andthe product chromatographed on silica to yield methyl4-(7'-hydroxy-3',7'-diethylnon- 2'-enyl0xy)benzoate.

The above process is repeatedwith the exception of using the esterslisted in Column 111 as the starting material to yield the correspondinghydroxy-substituted ester, that is:

methyl 4-(7-hydroxy-3',7-dimethyloct-2-enyloxy)- benzoate, methyl4-(7'-hydroxy-3'-methyl-7'-ethylnon- 2'enyloxy)-benzoate, methyl4-(7'-hydroxy-3,7-dimethylnon-2'-er1yloxy)-benzoate, methyl 4-( 8'-hydroxy-4'-methyl-8 '-ethyldec-3 enyloxy)benzoate, methyl4-(8'-hydr0xy-4,8'-dimethyldec-3'-enyloxy)-benzoate, methyl4-(8-hydroxy-4,8'-dimethylnon-3'-enyloxy)-benzoate, methyl 4-(5'-hydroxy-l ',5-dimethylhexanyloxy)- benzoate, and methyl 4-( 7-hydroxy-3 ',7 '-dimethyloctanyloxy )benzoate.

EXAMPLE 4 The process of Example 2, Part A, is repeated using benzylalcohol in place of ethanol to yield methyl 4- (3 ',7 -dimethyl-7 -benzyloxyoct-Z -enyloxy)-benzoate.

EXAMPLE 5 A. To a solution of 20.9 g. of the ethylene ketalofl-bromo-4-pentanone (obtained by treating l-bromo- 4-pentanone withethylene glycol in benzene in the presence of p-toluene-sulfonicacid) inml. of benzene is added 20 g. of triphenylphosphine. The mixture isheated at reflux temperature for two hours and then filtered. The solidmaterial thus-collected is washed with benzene, dried in vacuo and addedto 6.49 g. of butyl lithium in 50 ml. of dimethylsulfoxide. The mixtureis stirred until an orange solution is obtained and 38 g. of methylethyl ketone is then added. The mixture is stirred at about 25 for about8 hours, poured into water and then extracted with ether. The etherealphase is concentrated and the concentrate added to 0.1N solution ofhydrochloric acid in aqueous acetone and stirred for about 15 hours. Themixture is then poured into ice water and extracted with ethyl acetate.The extracts are combined, washed with water, dried over sodium sulfateand evaporated to yield 6-methyl- 5-octen-2-one (V111; R R methyl, Rethyl) which is purified by chromatography and separated into the cisand trans isomer.

By repeating the above process using the ethylene ketal of each ofl-bromo-S-hexanone and l-bromo-4- hexanone, there is obtained7-methyl-6-nonen-2-one and 7-methyl-6-nonen-3-one.

B. A mixture of 1 1.2 g. of diethyl carbomethoxymethyl-phosphonate in100 ml. of dimethylformamide is treated with 2.4 g. of sodium hydride.The mixture is stirred until the evolution of gas ceases and then 10 g.of 7-methyl-6-nonen-2-one is added slowly with stirring, maintainingtemperature below 30. The mixture is stirred for about 1 hour, thendiluted with water and then extracted with ether. The ethereal phase iswashed with water, dried over sodium sulfate and evaporated underreduced pressure to yield methyl 3,8-dimethyldeca-2,7-dienoate as amixture of isomers (trans,cis; trans,trans; cis,cis; and cis,trans)which are separated by chromatography.

C. Six grams of 6-methyl-5-octen-2-one is added to a solution of 3.0 g.of sodium borohydride, 80 ml. of methanol and 6 ml. of 2N sodiumhydroxide solution. After about 2 hours, acetic acid is added to destroyexcess sodium borohydride and the solution poured into water andextracted with ether. The combined ether extracts are washed withaqueous sodium bicarbonate, water and brine, dried and evaporated toyield 6-methyl-5-octen-2ol which is purified by chromatography.

Similarly, 7-methyl-6-nonen-2 one and 7-methyl-6- nonen-3-one is reducedto 7 methyl-6-nonen-2-ol and 7-methyl-6-nonen-3-ol.

Triphenylphosphite benzoylchloride (10 g.) is mixed with 1.9 g. of6-methyl-5-octen-2-ol and kept at room temperature overnight. The crudeproduct is washed with 2N sodium hydroxide and water and dried to yield2-chloro-6-methyl-5-octene.

Alternatively, the method of Example 1 is used to prepare the bromideand chloride.

D. A solution of 2 g. of methyl-3,8-dimethyldeca-2,7- dienoate in 20 ml.of dry ether is added with stirring to 0.4 g. of lithium aluminumhydride covered in ether at 0. After about one hour, 2.5 ml. ofaceticacid is added. The mixture is washed with ice water and the etherphase dried and evaporated to yield 3,8- dimethyldeca-2,7-dien-l-olwhich is treated with phosphorus tribromide to yieldl-bromo-3,8-dimethyldeca- 2,7-diene.

E. 6-Methyl-5-hepten-2-one is converted into4,8-dimethylnona-3,7-dienoic acid by reaction withB-carboxyethyltriphenylphosphonium chloride in dimethylsulfoxide usingthe method of H. S. Corey et al., J. Am. Chem. Soc. 86, 1884 (1964). Thetrans and cis isomer can be separated by chromatography at this point ora mixture of the two isomers employed in further reactions. The acid isthen converted into the acid chloride using thionyl chloride at roomtemperature or slightly higher temperature. The acid chloride is thentreated with an alcohol, such as methanol or ethanol, at a temperatureof about 40 for a few minutes to yield the ester, e.g., methyl4,8-dimethylnona-3,7-dienoate or ethyl 4,8-dimethylnona-3.7-dienoate.

By use of the above procedure, each of7-methyl-6- nonen-2-one and6-methyl-5-octen-2-one is converted into methyl4,9-dimethylundeca-3,8-dienoate and methyl4,8-dimethyldeca-3,7-dienoate, respectively.

Following the procedure of Part D above, each of the esters is reducedto the C-1 alcohol, i.e. 4,8- dimethylnona-3,7-dien-1-ol,4,9-dimethylundeca-3,8- dien-l-ol and 4,8-dimethyldeca-3,7-dien-l-ol andthen ethoxy-4,8-dimethylnon-3en-1-ol .10 to the C-1 bromide, namely,1-bromo-4,8-dimethylnona-3,7-diene, l-bromo-4,9-dimethylundeca-3,8-diene and 1-bromo-4,8-dimethyldeca-3,7-diene, respectively.

EXAMPLE 6 To a solution of 1.7 g. of methyl 4,8-dimethylnona-3,7-dienoate in 20 ml. of ethanol, cooled to about 0, is added asuspension of 2.3 g. of mercuric acetate in 50 ml. of ethanol, overabout 15 minutes. The reaction mixture is stirred for 2 hours and then,with cooling, 1.2 g. of potassium hydroxide in 20 ml. of ethanol isadded. Then 0.26 g. of sodium borohydride is added in small portions andstirring continued 30 minutes. The solution is decanted, concentrated tohalf volume, diluted with water and extracted with ether. The etherealphase is washed with water, dried over magnesium sulfate and the productchromatographed to yield 8- and methyl 8-ethoxy-4,8-dimethylnon-3-enoate.

The methyl ester, methyl 8-ethoxy-4,8-dimethylnon- 3-enoate is reducedusing lithium aluminum hydride following the procedure of Example 5,Part D, to the alcohol, 8-ethoxy-4,8-dimethylnon-3-enl-ol.

Using the foregoing procedure, each of methyl 4,9-dimethylundeca-3,8-dienoate and methyl 4,8-dimethyldeca-3,7-dienoate is'converted into 9-ethoxy4,9- dimethylundec-3-en-l-ol and 8-ethoxy-4,8-dimethyldec-3-en-l-ol. Following the procedure of, for example, Example1 (A and then B), the C-1 alcohols thus-obtained are converted into theC-1 bromide.

A suspension of 0.5 g. of 5 percent palladium-oncarbon catalyst in 50ml. of benzene is hydrogenated for 30 minutes. A mixture of 1.5 g. of9-ethoxy4,9- dimethylundec-3-en-1-ol in ml. of methanol is added andhydrogenated with agitation until the theoretical amount of hydrogen isabsorbed. The catalyst is removed by filtration and the solutionevaporated to yield 9-ethoxy-4,9-dimethylundecan-1-ol which is purifiedby chromatography.. The product is treated with phosphorus tribromide toyield l-bromo-9-ethoxy-4,9- dimethylundecane which can be used as thealkylating agentfor. EPQLMiQLQfiQLQPQUJ1 fth ptsst l vention o formulasI and 111.

The foregoing hydrogenation procedure can be used for preparing thesaturated derivatives of the present invention (i.e., when each of Z andZ is hydrogen) by hydrogenation of the final product or intermediatetherefor.

EXAMPLE 7 A mixture of l g. of methyl 4-(7'-ethoxy-3,7-dimethyloct-Z-enyloxy)benzoate, 60 ml. of methanol, 0.2 g. of sodiumcarbonate and 6 ml. of water is stirred at about 30 for about 3 hours.The mixture is diluted with water, neutralized and then extracted withether. The organic phase is washed with water, dried over sodium sulfateand evaporated at room temperature to yield4-(7'-ethoxy-3,7'-dimethyloct-2- enyloxy)benzoic acid which is purifiedby chromatography.

By use of the foregoing procedure, the other esters of the presentinvention can be hydrolyzed to the free acid.

EXAMPLE 8 One gram of thionyl chloride is added with stirring at roomtemperature to 0.5 g. of 4-(7-ethoxy-3,7- dimethyloct-2'-enyloxy)benzoicacid and the mixture heated at about 50 for 10 minutes. Excess thionylchloride is removed by evaporation. To the acid chloride is addedt-butyl alcohol (about two equivalents) and the mixture heated at about50 for minutes. Excess t-butyl alcohol is removed by evaporation toyield t-butyl 4-(7'-ethoxy-3,7-dimethyloct-2'-enyloxy)benzoate Byreplacing t-butyl alcohol with other alcohols, such as ethanol,isopropanol, cyclohexyl alcohol or benzyl cohol, the correspondingesters are obtained. What is claimed is: l. A compound selected fromthose of the formula:

n is three or four.

2. A compoundaccording to claim 1 wherein n is three and each of R R andR is methyl or ethyl.

3. A compound according to claim 2 wherein each of R and R is methyl; mis one; and R is ethyl.

4. A compound according to claim 2 wherein each of R and R is ethyl; Ris methyl or ethyl; and m is one.

5. A compound according to claim 2 wherein each of R and R is methyl; Ris ethyl; and m is one.

6. The compound, methyl 4-(3'-methyl-7'-ethyl-7'-ethoxynon-2'(trans)-enyloxy)benzoate, according to claim 1.

claim 1.

1. A COMPOUND SELECTED FROM THOSE OF THE FORMULA:
 2. A compoundaccording to claim 1 wherein n is three and each of R2, R3 and R4 ismethyl or ethyl.
 3. A compound according to claim 2 wherein each of R2,R3 and R4 is methyl; m is one; and R is ethyl.
 4. A compound accordingto claim 2 wherein each of R3 and R4 is ethyl; R2 is methyl or ethyl;and m is one.
 5. A compound according to claim 2 wherein each of R2 andR3 is methyl; R4 is ethyl; and m is one.
 6. The compound, methyl4-(3''-methyl-7''-ethyl-7''-ethoxynon-2''(trans)-enyloxy)benzoate,according to claim
 1. 7. The compound, methyl4-(3'',7''-dimethyl-7''-ethoxy-oct-2''(trans)-enyloxy)benzoate,according to claim
 1. 8. The compound, methyl4-(3'',7''-dimethyl-7''-ethoxynon-2''(trans)-enyloxy)benzoate, accordingto claim 1.